LED illumination apparatus

ABSTRACT

An LED illumination apparatus includes a first lighting module, a second lighting module, a lamp cup, a heat pipe, and a plurality of heat dissipation fins. The first and second lighting modules are connected with each other and emit light in opposite directions, in addition being received by the lamp cup. The lamp cup includes two reflecting surfaces arranged in symmetrical mirror fashion. The light emitting from the first and second lighting modules are directed to respective reflecting surfaces and reflected toward a same direction by the reflecting surfaces. The heat pipe is disposed in between the first and second lighting modules. The heat dissipation fins are fitted over the heat pipe. The heat generated by lighting modules would transmit to the heat pipe and be guided to the heat dissipation fins in order to accelerate cooling.

CROSS-REFERENCES TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a) on patent application No. 105101780 filed in Taiwan, R.O.C. onJan. 20, 2016, the entire contents of which are hereby incorporated byreference.

BACKGROUND

Technical Field

The instant disclosure relates to an LED illumination apparatus, inparticular to an LED illumination apparatus having heat dissipatingstructures.

Related Art

Head lights of rail cars are different from typical illuminationrequirements. By considering the weight and speed of rail cars, itsillumination is required to clearly illuminate objects far ahead on therail, unlike typical indoor illumination for close distance and largearea. Therefore, the light field associated with head lights of railcars must meets specific regulations. Since for rail cars, its headlights must achieve a certain level of illumination for a specificdistance and equivalent luminance, most rail cars today use conventionaltungsten light bulbs. However, since tungsten light bulbs have a shorterservice life and consume more power to reach certain illuminationintensity, one of the major consequences is excessive temperatures.

Since tungsten light bulbs generate more heat, when the light bulbs areexposed continuously under excessive temperature condition, the servicelife of light bulbs is shortened. Other issues include increasedreplacement rate and maintenance fee.

With the advancement in light emitting diodes (LEDs), many LED-basedproducts can replace existing tungsten light bulbs. But in order to meetthe requirements of head lights for rail cars, since the head lightsconsume more power, the manufacturing price of the product is alsohigher. This scenario leads to higher sales price on the market. Sincethe illumination angle for the LED is only 180° , unlike 360° fortungsten light bulbs, the current remedy is to place a lens in front ofthe LED to concentrate light beams off the LED. However, during themanufacturing stage, because such practice requires concentrating eachLED with the lens, the manufacturing process is more complicatedrelative to tungsten light bulbs. The manufacturing cost also increasessince multiple lenses must be used.

SUMMARY

In one embodiment, the LED illumination apparatus comprises a firstlight emitting module, a second light emitting module, a lamp cup, aheat pipe, and a plurality of heat-dissipating fins. The first lightingmodule includes a first base, a first circuit board, and a plurality offirst LEDs. The first LEDs are disposed on the first circuit board,while the first circuit board is disposed on a first surface of thefirst base. The second light emitting module includes a second base, asecond circuit board, and a plurality of second LEDs. The second LEDsare disposed on the second circuit board, while the second circuit boardis disposed on a first surface of the second base. Meanwhile, a secondsurface of the first base opposite to the first surface of the firstbase is mated with a second surface of the second base opposite to thefirst surface of the second base.

The lamp cup includes a first reflecting surface and a second reflectingsurface. The first and second reflecting surfaces are disposed in asymmetrical mirror fashion and received by the lamp cup. The heat pipeis penetratingly disposed in between the first and second bases andextends surroundingly toward the rear of the lamp cup. One end of eachof the heat-dissipating fins is fitted over the heat pipe, and theheat-dissipating fins are arranged surroundingly along the outer sidesurface of the lamp cup.

Based on the above structures, heat generation can be greatly reduced bythe use of LEDs as the light sources. The up-and-down arrangement of theLEDs allows more LEDs to be used in order to achieve requiredillumination intensity. By penetratingly dispose the heat pipe 40 inbetween the first and second bases 11 and 21, heat originated from thefirst and second bases 11 and 21 can be effectively directed to theheat-dissipating fins 50 via the heat pipe 40. Multiple heat-dissipatingfins 50 can effectively disperse heat to ambient air for enhancingheat-dissipation effect.

In some embodiments, the first LEDs of the first lighting module mayface toward the first reflecting surface, while the second LEDs of thesecond lighting module may face toward the second reflecting surface.Thus, the first lighting module emits light toward the first reflectingsurface, with the reflected light directed toward the front of the lampcup. Likewise, the second lighting module emits light toward the secondreflecting surface, with the reflected light directed toward the frontof the lamp cup. Hence, the reflected light can be more concentratedtoward a same direction, instead of overly dispersing. And no lenses areneeds for disposing in front of the LEDs for concentrating light beams.

In some embodiments, the number of the first LEDs is four and the fourfirst LEDs are arranged in a diamond-like pattern. Further, the firstLED disposed at the front end of the diamond-like pattern is the focalpoint of the first reflecting surface. Thus, for light beams directed tothe first reflecting surface by the first LEDs, a nearly hemisphericallight field can be formed upon reflection. Meanwhile, for the secondlighting module arranged oppositely of the first lighting module, sameconfiguration can be used as well. That is to say the number of thesecond LEDs is four and the four second LEDs are arranged in adiamond-like pattern. Thus, for light beams directed to the secondreflecting surface by the second LEDs, a nearly hemispherical lightfield can be formed upon reflection. Hence, for light beams emitted bythe first and second lighting modules, a nearly spherical light fieldcan be formed upon reflection by the first and second reflectingsurfaces.

In some embodiments, the heat pipe includes a straight portion, a bentportion, and a loop portion. The straight portion is disposed in betweenthe first and second bases, the bent portion is connected to thestraight portion, and the loop portion is connected to the bent portion.The straight portion in between the first and second bases can directheat to the bent and loop portions for heat dissipation.

In some embodiments, the bent and straight portions may jointly define a90° angle. Further, the loop portion may extend hemispherically anddefine a virtual central axis at the center of the hemisphere, with theaxis perpendicular to the radius thereof. The straight portion may bedisposed along the central axis of the loop portion. Since the straightportion of the heat pipe is arranged along the central axis of the lampcup, thus the loop portion of the heat pipe may be surroundinglydisposed along the outer circumferential surface of the lamp cup. Sincethe heat-dissipating fins are spacingly disposed along the loop portionof the heat pipe, the heat-dissipating fins can be surroundinglyarranged along the outer circumferential surface of the lamp cup. Thus,the overall volume of the LED illumination apparatus can be reducedwhile disposing as much dissipating fins as possible.

In some embodiments, the LED illumination apparatus further comprises afront cover, a glass cover, and a rear cover. The glass cover covers anopening defined by the lamp cup, the front cover is disposed in front ofthe lamp cup, and the rear cover is disposed at the rear of the lampcup. The front cover, lamp cup, and the rear cover may be screwedtogether sequentially.

In some embodiments, the LED illumination apparatus further comprises awater-proofing rubber ring, where the rubber ring is disposed on theouter circumferential surface of the opening of the lamp cup and inbetween the lamp cup and glass cover. The rubber ring can prevent wateror water vapor from intruding the lamp cup, so as to not damage thecircuit boards and LEDs.

The embodiments below provide detailed description of thecharacteristics and advantages of the instant disclosure, such that askilled person in the art may comprehend the technical features of theinstant disclosure and put into practice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an LED illumination apparatus for oneembodiment of the instant disclosure.

FIG. 2 is an exploded view of an LED illumination apparatus for oneembodiment of the instant disclosure.

FIG. 3 is a sectional view of an LED illumination apparatus for oneembodiment of the instant disclosure with some elements omitted.

FIG. 4 is a front view of an LED illumination apparatus for a secondembodiment of the instant disclosure with some elements omitted.

DETAILED DESCRIPTION

Please refer to FIGS. 1 to 3, where FIG. 1 is a schematic view of an LEDillumination apparatus for one embodiment of the instant disclosure,FIG. 2 is an exploded view of the LED illumination apparatus for thisembodiment of the instant disclosure, and FIG. 3 is a sectional view ofthe LED illumination apparatus for the same embodiment of the instantdisclosure with some elements omitted. For the instant embodiment, anLED illumination apparatus 100 comprises a first lighting module 10, asecond lighting module 20, a lamp cup 30, a heat pipe 40, a plurality ofheat dissipating fins 50, a front cover 60, a rear cover 70, and a glasscover 80.

The first lighting module 10 includes a first base 11, a first circuitboard 12, and a plurality of first light emitting diodes (LEDs) 13. Forthe instant embodiment, four first LEDs 13 are used for explanatorypurposes. In other embodiments, one or more first LED 13 may be disposeddepending on the required illumination. The four first LEDs 13 aredisposed on the first circuit board 12, which is secured to the firstbase 11. As shown in FIG. 2, the first base 11 of the instant embodimenthas a rectangular shaped tongue portion 111, where the first circuitboard 12 is disposed on a first surface of the tongue portion 111.

In addition, for the instant embodiment as shown in FIG. 2, the fourfirst LEDs 13 are arranged in a diamond-like pattern on the firstcircuit board 12. The first LEDs 13 disposed at the tips of thediamond-like pattern are arranged on the front and rear ends of thefirst circuit board 12, respectively. Here, the front end of the firstcircuit board 12 refers to the tip portion on the left-hand side in FIG.3, while the rear end thereof refers to another tip portion relative tothe front end, that is to say the tip portion on the right-hand side inFIG. 3.

The second lighting module 20 includes a second base 21, a secondcircuit board 22, and a plurality of second LEDs 23. For the instantembodiment, four second LEDs 23 are used for explanatory purposes. Inother embodiments, one or more second LED 23 may be disposed dependingon the required illumination. The four second LEDs 23 are disposed onthe second circuit board 22, which is secured to the second base 21. Asshown in FIG. 2, the second base 21 of the instant embodiment isrectangular shaped, where the second circuit board 22 is disposed on afirst surface of the second base 21.

Identically, for the instant embodiment as shown in FIG. 2, the foursecond LEDs 23 are arranged in a diamond-like pattern on the secondcircuit board 22. The second LEDs 23 disposed at the tips of thediamond-like pattern are arranged on the front and rear ends of thesecond circuit board 22, respectively. Here, the front end of the secondcircuit board 22 refers to the tip portion on left-hand side in FIG. 3,while the rear end thereof refers to another tip portion relative to thefront end. That is to say the tip portion on the right-hand side in FIG.3.

As illustrated in FIG. 2, a second surface of the tongue portion 111 ofthe first base 11 opposite to the first surface of the tongue portion111 is mated with a second surface of the second base 21 opposite to thefirst surface of the second base 21. As shown in FIG. 3, after theassembling process is completed, the first LEDs 13 and the second LEDs23 face opposite directions.

Please refer to FIGS. 2˜4, where FIG. 4 is a front view of the LEDillumination apparatus of the instant embodiment omitting the frontcover 60, rear cover 70, and glass cover 80. The lamp cup 30 of theinstant embodiment includes a first reflecting surface 31, a secondreflecting surface 32, and an opening 33. The first reflecting surface31 and the second reflecting surface 32 are arranged essentially in asymmetrical mirror fashion. The front end of the lamp cup 30 defines anopening 33 for emitting light therefrom. For the instant embodiment, thelast described front end of the lamp cup 30 refers to the left-hand sidedirection in FIG. 3, while the rear end of the lamp cup 30 refers to theright-hand side direction in FIG. 3. The outer side of the lamp cup 30refers to the surface of the lamp cup 30 on the right-hand side of FIG.3, while the inner side of the lamp cup 30 refers to the concaved sideof the lamp cup 30 on the left-hand side of FIG. 3, that is thelocations occupied by the first and second reflecting surfaces 31 and32.

The first and second reflecting surfaces 31 and 32 can each has its owncurvature. For the instant embodiment, they have the same curvatures andform a symmetrical mirror after the assembling process is done. As shownin FIG. 4, the connecting sides of the first and second reflectingsurfaces 31 and 32 are formed in a straight line fashion, with a lengthd of this straight line portion being approximately equal to thethickness of the assembled first and second bases 11 and 21.

As shown in FIGS. 3 and 4, the first and second lighting modules 10 and20 are received by the lamp cup 30. The first LEDs 13 of the firstlighting module 10 are arranged in such a way that they face toward thefirst reflecting surface 31. The second LEDs 23 of the second lightingmodule 20 are arranged in such a way that they face toward the secondreflecting surface 32. After light is emitted toward the firstreflecting surface 31 from the first LEDs 13, the reflected light emitsin a direction toward the opening 33. Likewise, after light is emittedtoward the second reflecting surface 32 from the second LEDs 23, thereflected light also emits in a direction toward the opening 33. Afterlight beams emitted by the first LEDs 13 are reflected, the light raysform a light field that is hemispherically shaped. Likewise, after lightbeams emitted by the second LEDs 23 are reflected, the light rays form alight field that is hemispherically shaped. The two hemisphericallyshaped light fields in the up and down orientation jointly form a lightfield that is approximately spherically shaped.

Furthermore, to make the reflected light source more concentrated andilluminates farther distance away, the first LED 13 disposed at thefront end of the diamond-like pattern can be arranged at the focal pointof the first reflecting surface 31. Likewise, the second LED 23 disposedat the front end of the diamond-like pattern can be arranged at thefocal point of the second reflecting surface 32. In addition, for easyassembling and minimizing change in reflected light source intensity dueto assembling errors, the intersection between two diagonals of thediamond-like pattern and the middle point of the LED disposed at thefront end of the diamond-like pattern may match the focal point locationof the reflecting surface.

Please refer to FIGS. 2 and 3. In addition to the rectangular tongueshaped portion 111, the first base 11 also has a circular assemblingportion 112. The assembling portion 112 is connected to the rear end ofthe tongue portion 111. As shown in FIG. 3, when the first lightingmodule 10 is assembled to the lamp cup 30, the tongue portion 111 of thefirst base 11 protrudes into the lamp cup 30 from the rear thereof,while the assembling portion 112 presses against the rear of the lampcup 30. Therefore, by adjusting the length of the tongue portion 111 andthe position of the first LEDs 13 on the tongue portion 111, when theassembling portion 112 is pressed against the lamp cup 30, the locationof the focal point of the first lighting module 10 can match the focalpoint of the first reflecting surface 31. In addition, the focal pointof the second lighting module 20 connected to the first lighting module10 matches the focal point of the second reflecting surface 32. Thus,the positioning of various parts during the assembling process becomeseasier, which reduces the chances of inadequate light intensity afterreflection due to assembling errors.

Next, please refer to FIGS. 1˜3. The heat pipe 40 is protrudinglydisposed in between the first and second bases 11 and 21, in addition toextending toward the rear of the lamp cup 30. For the instantembodiment, the heat pipe 40 includes a straight portion 41, a bentportion 42, and a loop portion 43. The straight portion 41, bent portion42, and loop portion 43 are connected in sequence. The straight portion41 is penetratingly disposed in between the first and second bases 11and 21, for directing the heat generated by the first and second bases11 and 21. The bent portion 42 and straight portion 41 jointly define anapproximately 90° angle, while the loop portion 43 follows ahemispherical path.

As shown in FIG. 2, for the loop portion 43 that extendshemispherically, it defines a virtual central axis C at the center ofthe hemisphere, with the central axis C perpendicular to the radiusthereof. The straight portion 41 is disposed along the central axis C.Please refer to FIG. 4 in conjunction. After assembling, the straightportion 41 is arranged at the center position of the lamp cup 30, suchthat the loop portion 43 is parallel to the opening 33 of the lamp cup30 and loops around the outer side surface of the lamp cup 30. For otherembodiments, the loop portion 43 may conform to the shape of the outerside surface of the lamp cup 30, such that the loop portion 43 can becurve-shaped in matching the outer circumferential shape of a radialcross-sectional surface of the outer ring-shaped surface of the lamp cup30.

One end of each of the heat dissipating fins 50 is fitted over the heatpipe 40, with the fins 50 arranged surroundingly along the outer sidesurface of the lamp cup 30. As can be seen from FIGS. 1˜3, the fins 50are arranged on the loop portion 43 of the heat pipe 40. A particularclearance is defined between adjacent fins 50, with each fin 50 being athin slice having a particular surface area, such that heat can bedispersed onto each of the fins 50. Thus, the fins 50 can have morecontact surface with the air, which allows heat conducted to the fins 50can be dispersed into air more quickly. Since the fins 50 are fittedover the heat pipe 40, the heat generated by the first and secondlighting modules 10 and 20 can be guided to the fins 50 via the heatpipe 40 for dispersion.

As shown in FIG. 3, to allow the fins 50 to have greater heatdissipating areas, while utilizing the inner space of the LEDillumination apparatus, each of the fins 50 is slightlytrapezoid-shaped. The slanting surface is arranged on the outer sidesurface of the lamp cup 30. Meanwhile, each of the fins 50 has anextending rectangular portion, which is disposed behind the assemblingportion 112 of the first base 11. This rectangular portion also acts todirect the heat of the assembling portion 112 to the fins 50. Each ofthe fins 50 defines a thru hole at an end portion thereof for fittingthe heat pipe 40. As shown in FIGS. 1 and 2, after the fins 50 have beenfitted over the loop portion 43 of the heat pipe 40, the fins 50 arearranged surroundingly along the loop portion 43. After assembling, thefins 50 define a shape that features the surrounding arrangement overthe outer side surface of the lamp cup 30. By arranging the fins 50 thisway, the LED illumination apparatus 100 does not need to increase itsvolume significantly while still maintaining a certain size andutilizing the available space.

Please refer to FIG. 2. A water-proofing rubber ring 34 can be disposedon the outer circumferential surface of the opening 33 in front of thelamp cup 30. Then, the glass cover 80 can cover the opening 33. By beingin between the lamp cup 30 and the glass cover 80, the rubber ring 34prevents water or water vapor from intruding the lamp cup 30. Next, thefront cover 60 is fitted in front of the lamp cup 30, while the rearcover 70 is fitted in the rear of the lamp cup 30. Then, a plurality ofscrews 90 can be used to secure the front cover 60, lamp cup 30, andrear cover 70 in sequence. In particular, the rear cover 70 can enclosethe fins 50 in the rear, with the shape of the rear cover 70 mating tothe shape of the outer side surfaces of the fins 50.

Based on the above structures, heat generation can be greatly reduced bythe use of LEDs as the light sources. The up-and-down arrangement of theLEDs allows more LEDs to be used in order to achieve requiredillumination intensity. By manipulating the way that LEDs are arrangedand its positions, light beams emitted by the LEDs can be effectivelyreflected outwardly as much as possible. Meanwhile, by adjusting theshape of curvature of the reflecting surfaces, the reflected lightsources can be more concentrated and provides nearly spherical lightfield. In addition, by penetratingly dispose the heat pipe 40 in betweenthe first and second bases 11 and 21, heat originated from the first andsecond bases 11 and 21 can be effectively directed to theheat-dissipating fins 50 via the heat pipe 40. Multiple heat-dissipatingfins 50 can effectively disperse heat to ambient air for enhancingheat-dissipation effect.

While the instant disclosure has been described by way of example and interms of the preferred embodiments, it is to be understood that theinstant disclosure needs not be limited to the disclosed embodiments.For anyone skilled in the art, various modifications and improvementswithin the spirit of the instant disclosure are covered under the scopeof the instant disclosure. The covered scope of the instant disclosureis based on the appended claims.

What is claimed is:
 1. A light-emitting diode (LED) illuminationapparatus, comprising: a first light emitting module including a firstbase, a first circuit board, and four first LEDs, the four first LEDsbeing disposed on the first circuit board, faced toward the firstreflecting surface and arranged in a diamond-like pattern, the firstcircuit board being disposed on a first surface of the first base; asecond light emitting module including a second base, a second circuitboard, and at least one second LED, the second LED being disposed on thesecond circuit board and faced toward the second reflecting surface, thesecond circuit board being disposed on a first surface of the secondbase, wherein a second surface of the first base opposite to the firstsurface of the first base is mated with a second surface of the secondbase opposite to the first surface of the second base; a lamp cupincluding a first reflecting surface and a second reflecting surface,the first and second reflecting surfaces being disposed in a symmetricalmirror fashion, the first and second lighting modules being received bythe lamp cup; a heat pipe penetratingly disposed in between the firstand second bases, the heat pipe protruding towards the rear of the lampcup and then extending surroundingly around the heat pipe; and aplurality of heat-dissipating fins, with one end of each of theheat-dissipating fins fitted over the heat pipe, the heat-dissipatingfins being arranged surroundingly along the outer side surface of thelamp cup; wherein the intersection between two diagonals of thediamond-like pattern and a middle point of the first LED disposed at thefront end of the diamond-like pattern match the focal point location ofthe first reflecting surface.
 2. The LED illumination apparatus of claim1, wherein the heat pipe includes a straight portion, a bent portion,and a loop portion, and wherein the straight portion is disposed inbetween the first and second bases, the bent portion is connected to thestraight portion, and the loop portion is connected to the bent portion.3. The LED illumination apparatus of claim 2, wherein the loop portionextends hemispherically.
 4. The LED illumination apparatus of claim 3wherein the straight portion is disposed along a central axis of theloop portion.
 5. The LED illumination apparatus of claim 1, furthercomprising a front cover, a glass cover, and a rear cover, wherein theglass cover covers an opening defined by the lamp cup, the front coveris disposed in front of the lamp cup, and the rear cover is disposed atthe rear of the lamp cup.
 6. The LED illumination apparatus of claim 5,further comprising a water-proofing rubber ring, wherein the rubber ringis disposed on the outer circumferential surface of the opening of thelamp cup and in between the lamp cup and glass cover.
 7. Alight-emitting diode (LED) illumination apparatus, comprising: a firstlight emitting module including a first base, a first circuit board, andat least one first LED, the first LED being disposed on the firstcircuit board, the first circuit board being disposed on a first surfaceof the first base; a second light emitting module including a secondbase, a second circuit board, and at least one second LED, the secondLED being disposed on the second circuit board, the second circuit boardbeing disposed on a first surface of the second base, wherein a secondsurface of the first base opposite to the first surface of the firstbase is mated with a second surface of the second base opposite to thefirst surface of the second base; a lamp cup including a firstreflecting surface and a second reflecting surface, the first and secondreflecting surfaces being disposed in a symmetrical mirror fashion, thefirst and second lighting modules being received by the lamp cup; a heatpipe penetratingly disposed in between the first and second bases, theheat pipe protruding towards the rear of the lamp cup and then extendingsurroundingly around the heat pipe; and a plurality of heat-dissipatingfins, with one end of each of the heat-dissipating fins fitted over theheat pipe, the heat-dissipating fins being arranged surroundingly alongthe outer side surface of the lamp cup; wherein the heat pipe includes astraight portion, a bent portion, and a loop portion, and wherein thestraight portion is disposed in between the first and second bases, thebent portion is connected to the straight portion, and the loop portionis connected to the bent portion.
 8. The LED illumination apparatus ofclaim 7, wherein the loop portion extends hemispherically.
 9. The LEDillumination apparatus of claim 8, wherein the straight portion isdisposed along a central axis of the loop portion.
 10. The LEDillumination apparatus of claim 7, further comprising a front cover, aglass cover, and a rear cover, wherein the glass cover covers an openingdefined by the lamp cup, the front cover is disposed in front of thelamp cup, and the rear cover is disposed at the rear of the lamp cup.11. The LED illumination apparatus of claim 10, further comprising awater-proofing rubber ring, wherein the rubber ring is disposed on theouter circumferential surface of the opening of the lamp cup and inbetween the lamp cup and glass cover.
 12. The LED illumination apparatusof claim 7, wherein the first LED of the first lighting module facestoward the first reflecting surface, and the second LED of the secondlighting module faces toward the second reflecting surface.
 13. The LEDillumination apparatus of claim 12, wherein the number of the first LEDsis four and the four first LEDs are arranged in a diamond-like pattern.14. The LED illumination apparatus of claim 13, wherein the first LEDdisposed at the front end of the diamond-like pattern is located at thefocal point of the first reflecting surface.